Saturday, August 31, 2019

In this tutorial, I will show you how to rollback from a bad distro update of Fedora 31 to the old one Fedora 30.
If you follow this tutorial and you got errors then your dnf tool will have problems with update process.
After I follow the tutorial I got many packages and errors.
I try to fix with this but not work:

[root@desk mythcat]# dnf system-upgrade download --refresh --releasever=31
--setopt=module_platform_id=platform:f31 --skip-broken
Before you continue to ensure that your system is fully upgraded by running "dnf
--refresh upgrade". Do you want to continue [y/N]: y
...

Because the Fedora 31 is not available I need to roll back to my old Fedora 30. This are steps I used to fix this issue:

The pkcon tool refresh the cached information about available updates and set the maximum acceptable age for cached metadata, in seconds.
The option of dnf tool clean all --releasever=32 will clean all packages from fc32.
I used this command to see what packages with errors and the repo with problems:

Wednesday, August 21, 2019

Linux Malware Detect (LMD) is a malware scanner for Linux released under the GNU GPLv2 license, that is designed around the threats faced in shared hosted environments.
This tool is provided by R-fx Networks.
Let's install and test it:

Tuesday, August 20, 2019

I try to install the last version of PHP version 7.4.0beta2 with Fedora 30 distro the LXQt environment.
I have not used this programming language for a few years and it is a good issue to remember it.
I download teh archive from the official website and I run these commands:

checking for sqlite3 > 3.7.4... no
configure: error: Package requirements (sqlite3 > 3.7.4) were not met:
Package 'sqlite3', required by 'virtual:world', not found
Consider adjusting the PKG_CONFIG_PATH environment variable if you
installed software in a non-standard prefix.

[mythcat@desk php-7.4.0beta2]$ ./configure --prefix=$HOME/local
...
config.status: executing default commands
+--------------------------------------------------------------------+
| License: |
| This software is subject to the PHP License, available in this |
| distribution in the file LICENSE. By continuing this installation |
| process, you are bound by the terms of this license agreement. |
| If you do not agree with the terms of this license, you must abort |
| the installation process at this point. |
+--------------------------------------------------------------------+
Thank you for using PHP.
[mythcat@desk php-7.4.0beta2]$ make
...
Build complete.
Don't forget to run 'make test'.
[mythcat@desk php-7.4.0beta2]$ make install
...
[mythcat@desk php-7.4.0beta2]$ make test
...
FAILED TEST SUMMARY
---------------------------------------------------------------------
php://fd wrapper: invalid file descriptor [ext/standard/tests/file/php_fd_wrapper_04.phpt]
=====================================================================
You may have found a problem in PHP.
This report can be automatically sent to the PHP QA team at
http://qa.php.net/reports and http://news.php.net/php.qa.reports
This gives us a better understanding of PHP's behavior.
If you don't want to send the report immediately you can choose
option "s" to save it. You can then email it to qa-reports@lists.php.net later.
Do you want to send this report now? [Yns]: s
sh: autoconf: command not found
Please send /home/mythcat/php/php-7.4.0beta2/php_test_results_20190819_2038.txt to qa-reports@lists.php.net
manually, thank you.
make: *** [Makefile:201: test] Error 1
[mythcat@desk php-7.4.0beta2]$ export PATH=$HOME/local/bin:$PATH
[mythcat@desk php-7.4.0beta2]$ . ~/.bash_profile
[mythcat@desk php-7.4.0beta2]$ which php
~/local/bin/php
[mythcat@desk php-7.4.0beta2]$ php -v
PHP 7.4.0beta2 (cli) (built: Aug 19 2019 23:31:07) ( NTS )
Copyright (c) The PHP Group
Zend Engine v3.4.0-dev, Copyright (c) Zend Technologies

Wednesday, August 14, 2019

In computing, a firewall is a network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules.[1] A firewall typically establishes a barrier between a trusted internal network and untrusted external network, such as the Internet.[2], see the wikipedia.
In this short tutorial about the Fedora firewall subject, I will show you how you can use firewall commands to set it.
The install is simple with dnf tool:

Friday, August 9, 2019

The Visual Studio Code editor is officially distributed as a Snap package in the Snap Store.
It runs well on the Fedora distro, but with my Window operating system is crash often.
I like to develop my python projects like Flask and Django with this editor.
You can install it very easy on Fedora with the dnf tool:

Tuesday, August 6, 2019

GnuPG allows you to encrypt and sign your data and communications; it features a versatile key management system, along with access modules for all kinds of public key directories. see the official webpage.
Today I test it with Fedora 30 distro and works well.
You can find this tool in many Linux distros.
Let's install it with dnf tool.

This tool can be run with the gpg command and arguments:
Let's see some example:

[mythcat@desk ~]$ gpg --list-secret-keys
[mythcat@desk ~]$ gpg --list-keys
[mythcat@desk ~]$ gpg --full-generate-key
gpg (GnuPG) 2.2.17; Copyright (C) 2019 Free Software Foundation, Inc.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Please select what kind of key you want:
(1) RSA and RSA (default)
(2) DSA and Elgamal
(3) DSA (sign only)
(4) RSA (sign only)
Your selection?
Your selection? 1
RSA keys may be between 1024 and 4096 bits long.
What keysize do you want? (2048)
Requested keysize is 2048 bits
Please specify how long the key should be valid.
0 = key does not expire
= key expires in n days
w = key expires in n weeks
m = key expires in n months
y = key expires in n years
Key is valid for? (0) 0
Key does not expire at all
Is this correct? (y/N) y
GnuPG needs to construct a user ID to identify your key.
Real name: Catalin George Festila
Email address: catafest@yahoo.com
Comment: test gpg key
You selected this USER-ID:
...
Change (N)ame, (C)omment, (E)mail or (O)kay/(Q)uit? O
Enter password for protection
We need to generate a lot of random bytes. It is a good idea to perform
some other action (type on the keyboard, move the mouse, utilize the
disks) during the prime generation; this gives the random number
generator a better chance to gain enough entropy.
...

This command is normally only used interactive to generate a new key pair.

[mythcat@desk ~]$ gpg --gen-key
gpg (GnuPG) 2.2.17; Copyright (C) 2019 Free Software Foundation, Inc.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Note: Use "gpg --full-generate-key" for a full featured key generation dialog.
GnuPG needs to construct a user ID to identify your key.
Real name:
...